YOLO11改进 | 融合改进 | C3k2融合 Context Anchor Attention 【两个版本融合-独家创新】

秋招面试专栏推荐 :深度学习算法工程师面试问题总结【百面算法工程师】——点击即可跳转


????????????本专栏所有程序均经过测试,可成功执行????????????


本文给大家带来的教程是将YOLO11的C3k2替换为融合结构来提取特征。文章在介绍主要的原理后,将手把手教学如何进行模块的代码添加和修改,并将修改后的完整代码放在文章的最后,方便大家一键运行,小白也可轻松上手实践。以帮助您更好地学习深度学习目标检测YOLO系列的挑战。 

专栏地址:YOLO11入门 + 改进涨点——点击即可跳转 欢迎订阅

目录

1.论文

2. C3k2_CAA代码实现

2.1 将C3k2_CAA添加到YOLO11中

2.2 更改init.py文件

2.3 添加yaml文件

2.4 在task.py中进行注册

2.5 执行程序

3.修改后的网络结构图

4. 完整代码分享

5. GFLOPs

6. 进阶

7.总结


1.论文

论文地址:Poly Kernel Inception Network for Remote Sensing Detection——点击即可跳转

官方代码:官方代码仓库点击即可跳转

2. C3k2_CAA代码实现

2.1 将C3k2_CAA添加到YOLO11中

关键步骤一:在ultralytics\ultralytics\nn\modules下面新建文件夹models,在文件夹下新建C3k2_CAA.py,粘贴下面代码

from timm.models.layers import DropPath
from torch import nn
from ultralytics.nn.modules.conv import Conv
import torch


# CVPR2024 PKINet
class CAA(nn.Module):
    def __init__(self, ch, h_kernel_size = 11, v_kernel_size = 11) -> None:
        super().__init__()
        
        self.avg_pool = nn.AvgPool2d(7, 1, 3)
        self.conv1 = Conv(ch, ch)
        self.h_conv = nn.Conv2d(ch, ch, (1, h_kernel_size), 1, (0, h_kernel_size // 2), 1, ch)
        self.v_conv = nn.Conv2d(ch, ch, (v_kernel_size, 1), 1, (v_kernel_size // 2, 0), 1, ch)
        self.conv2 = Conv(ch, ch)
        self.act = nn.Sigmoid()
    
    def forward(self, x):
        attn_factor = self.act(self.conv2(self.v_conv(self.h_conv(self.conv1(self.avg_pool(x))))))
        return attn_factor * x
 
 
class Bottleneck_CAA(nn.Module):
    def __init__(self, dim, mlp_ratio=3, drop_path=0.):
        super().__init__()
        self.dwconv = Conv(dim, dim, 7, g=dim, act=False)
        self.f1 = nn.Conv2d(dim, mlp_ratio * dim, 1)
        self.f2 = nn.Conv2d(dim, mlp_ratio * dim, 1)
        self.g = Conv(mlp_ratio * dim, dim, 1, act=False)
        self.dwconv2 = nn.Conv2d(dim, dim, 7, 1, (7 - 1) // 2, groups=dim)
        self.act = nn.ReLU6()
        self.drop_path = DropPath(drop_path) if drop_path > 0. else nn.Identity()
 
    def forward(self, x):
        input = x
        x = self.dwconv(x)
        x1, x2 = self.f1(x), self.f2(x)
        x = self.act(x1) * x2
        x = self.dwconv2(self.g(x))
        x = input + self.drop_path(x)
        return x
 
class Bottleneck_CAAv2(Bottleneck_CAA):
    def __init__(self, dim, mlp_ratio=3, drop_path=0):
        super().__init__(dim, mlp_ratio, drop_path)
        
        self.attention = CAA(mlp_ratio * dim)
    
    def forward(self, x):
        input = x
        x = self.dwconv(x)
        x1, x2 = self.f1(x), self.f2(x)
        x = self.act(x1) * x2
        x = self.dwconv2(self.g(self.attention(x)))
        x = input + self.drop_path(x)
        return x


class Bottleneck(nn.Module):
    """Standard bottleneck."""

    def __init__(self, c1, c2, shortcut=True, g=1, k=(3, 3), e=0.5):
        """Initializes a standard bottleneck module with optional shortcut connection and configurable parameters."""
        super().__init__()
        c_ = int(c2 * e)  # hidden channels
        self.cv1 = Conv(c1, c_, k[0], 1)
        self.cv2 = Conv(c_, c2, k[1], 1, g=g)
        self.add = shortcut and c1 == c2

    def forward(self, x):
        """Applies the YOLO FPN to input data."""
        return x + self.cv2(self.cv1(x)) if self.add else self.cv2(self.cv1(x))
    
class C2f(nn.Module):
    """Faster Implementation of CSP Bottleneck with 2 convolutions."""

    def __init__(self, c1, c2, n=1, shortcut=False, g=1, e=0.5):
        """Initializes a CSP bottleneck with 2 convolutions and n Bottleneck blocks for faster processing."""
        super().__init__()
        self.c = int(c2 * e)  # hidden channels
        self.cv1 = Conv(c1, 2 * self.c, 1, 1)
        self.cv2 = Conv((2 + n) * self.c, c2, 1)  # optional act=FReLU(c2)
        self.m = nn.ModuleList(Bottleneck(self.c, self.c, shortcut, g, k=((3, 3), (3, 3)), e=1.0) for _ in range(n))

    def forward(self, x):
        """Forward pass through C2f layer."""
        y = list(self.cv1(x).chunk(2, 1))
        y.extend(m(y[-1]) for m in self.m)
        return self.cv2(torch.cat(y, 1))

    def forward_split(self, x):
        """Forward pass using split() instead of chunk()."""
        y = list(self.cv1(x).split((self.c, self.c), 1))
        y.extend(m(y[-1]) for m in self.m)
        return self.cv2(torch.cat(y, 1))

class C3k2(C2f):
    """Faster Implementation of CSP Bottleneck with 2 convolutions."""

    def __init__(self, c1, c2, n=1, c3k=False, e=0.5, g=1, shortcut=True):
        """Initializes the C3k2 module, a faster CSP Bottleneck with 2 convolutions and optional C3k blocks."""
        super().__init__(c1, c2, n, shortcut, g, e)
        self.m = nn.ModuleList(
            C3k(self.c, self.c, 2, shortcut, g) if c3k else Bottleneck(self.c, self.c, shortcut, g) for _ in range(n)
        )

class C3(nn.Module):
    """CSP Bottleneck with 3 convolutions."""

    def __init__(self, c1, c2, n=1, shortcut=True, g=1, e=0.5):
        """Initialize the CSP Bottleneck with given channels, number, shortcut, groups, and expansion values."""
        super().__init__()
        c_ = int(c2 * e)  # hidden channels
        self.cv1 = Conv(c1, c_, 1, 1)
        self.cv2 = Conv(c1, c_, 1, 1)
        self.cv3 = Conv(2 * c_, c2, 1)  # optional act=FReLU(c2)
        self.m = nn.Sequential(*(Bottleneck(c_, c_, shortcut, g, k=((1, 1), (3, 3)), e=1.0) for _ in range(n)))

    def forward(self, x):
        """Forward pass through the CSP bottleneck with 2 convolutions."""
        return self.cv3(torch.cat((self.m(self.cv1(x)), self.cv2(x)), 1))

class C3k(C3):
    """C3k is a CSP bottleneck module with customizable kernel sizes for feature extraction in neural networks."""

    def __init__(self, c1, c2, n=1, shortcut=True, g=1, e=0.5, k=3):
        """Initializes the C3k module with specified channels, number of layers, and configurations."""
        super().__init__(c1, c2, n, shortcut, g, e)
        c_ = int(c2 * e)  # hidden channels
        # self.m = nn.Sequential(*(RepBottleneck(c_, c_, shortcut, g, k=(k, k), e=1.0) for _ in range(n)))
        self.m = nn.Sequential(*(Bottleneck(c_, c_, shortcut, g, k=(k, k), e=1.0) for _ in range(n)))


class C3k2_CAA(C2f):
    """Faster Implementation of CSP Bottleneck with 2 convolutions."""

    def __init__(self, c1, c2, n=1, c3k=False, e=0.5, g=1, shortcut=True):
        """Initializes the C3k2 module, a faster CSP Bottleneck with 2 convolutions and optional C3k blocks."""
        super().__init__(c1, c2, n, shortcut, g, e)
        self.m = nn.ModuleList(
            C3k(self.c, self.c, 2, shortcut, g) if c3k else Bottleneck_CAA(self.c) for _ in range(n)
        )


class C3k2_CAA_v2(C2f):
    """Faster Implementation of CSP Bottleneck with 2 convolutions."""

    def __init__(self, c1, c2, n=1, c3k=False, e=0.5, g=1, shortcut=True):
        """Initializes the C3k2 module, a faster CSP Bottleneck with 2 convolutions and optional C3k blocks."""
        super().__init__(c1, c2, n, shortcut, g, e)
        self.m = nn.ModuleList(
            C3k(self.c, self.c, 2, shortcut, g) if c3k else Bottleneck_CAAv2(self.c) for _ in range(n)
        )

2.2 更改init.py文件

关键步骤二:在文件ultralytics\ultralytics\nn\modules\models文件夹下新建__init__.py文件,先导入函数

然后在下面的__all__中声明函数

2.3 添加yaml文件

关键步骤三:在/ultralytics/ultralytics/cfg/models/11下面新建文件yolo11_GCNet.yaml文件,粘贴下面的内容【C3k2_DWRv2直接替换C3k2_DWR即可,我不重复写yaml文件了

  • 目标检测
# Ultralytics YOLO ????, AGPL-3.0 license
# YOLO11 object detection model with P3-P5 outputs. For Usage examples see https://docs.ultralytics.com/tasks/detect

# Parameters
nc: 80 # number of classes
scales: # model compound scaling constants, i.e. 'model=yolo11n.yaml' will call yolo11.yaml with scale 'n'
  # [depth, width, max_channels]
  n: [0.50, 0.25, 1024] # summary: 319 layers, 2624080 parameters, 2624064 gradients, 6.6 GFLOPs
  s: [0.50, 0.50, 1024] # summary: 319 layers, 9458752 parameters, 9458736 gradients, 21.7 GFLOPs
  m: [0.50, 1.00, 512] # summary: 409 layers, 20114688 parameters, 20114672 gradients, 68.5 GFLOPs
  l: [1.00, 1.00, 512] # summary: 631 layers, 25372160 parameters, 25372144 gradients, 87.6 GFLOPs
  x: [1.00, 1.50, 512] # summary: 631 layers, 56966176 parameters, 56966160 gradients, 196.0 GFLOPs

# YOLO11n backbone
backbone:
  # [from, repeats, module, args]
  - [-1, 1, Conv, [64, 3, 2]] # 0-P1/2
  - [-1, 1, Conv, [128, 3, 2]] # 1-P2/4
  - [-1, 2, C3k2, [256, False, 0.25]]
  - [-1, 1, Conv, [256, 3, 2]] # 3-P3/8
  - [-1, 2, C3k2, [512, False, 0.25]]
  - [-1, 1, Conv, [512, 3, 2]] # 5-P4/16
  - [-1, 2, C3k2, [512, True]]
  - [-1, 1, Conv, [1024, 3, 2]] # 7-P5/32
  - [-1, 2, C3k2, [1024, True]]
  - [-1, 1, SPPF, [1024, 5]] # 9
  - [-1, 2, C2PSA, [1024]] # 10

# YOLO11n head
head:
  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 6], 1, Concat, [1]] # cat backbone P4
  - [-1, 2, C3k2_CAA, [512, False]] # 13

  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 4], 1, Concat, [1]] # cat backbone P3
  - [-1, 2, C3k2_CAA, [256, False]] # 16 (P3/8-small)

  - [-1, 1, Conv, [256, 3, 2]]
  - [[-1, 13], 1, Concat, [1]] # cat head P4
  - [-1, 2, C3k2_CAA, [512, False]] # 19 (P4/16-medium)

  - [-1, 1, Conv, [512, 3, 2]]
  - [[-1, 10], 1, Concat, [1]] # cat head P5
  - [-1, 2, C3k2_CAA, [1024, True]] # 22 (P5/32-large)

  - [[16, 19, 22], 1, Detect, [nc]] # Detect(P3, P4, P5)
  • 语义分割
# Ultralytics YOLO ????, AGPL-3.0 license
# YOLO11 object detection model with P3-P5 outputs. For Usage examples see https://docs.ultralytics.com/tasks/detect

# Parameters
nc: 80 # number of classes
scales: # model compound scaling constants, i.e. 'model=yolo11n.yaml' will call yolo11.yaml with scale 'n'
  # [depth, width, max_channels]
  n: [0.50, 0.25, 1024] # summary: 319 layers, 2624080 parameters, 2624064 gradients, 6.6 GFLOPs
  s: [0.50, 0.50, 1024] # summary: 319 layers, 9458752 parameters, 9458736 gradients, 21.7 GFLOPs
  m: [0.50, 1.00, 512] # summary: 409 layers, 20114688 parameters, 20114672 gradients, 68.5 GFLOPs
  l: [1.00, 1.00, 512] # summary: 631 layers, 25372160 parameters, 25372144 gradients, 87.6 GFLOPs
  x: [1.00, 1.50, 512] # summary: 631 layers, 56966176 parameters, 56966160 gradients, 196.0 GFLOPs

# YOLO11n backbone
backbone:
  # [from, repeats, module, args]
  - [-1, 1, Conv, [64, 3, 2]] # 0-P1/2
  - [-1, 1, Conv, [128, 3, 2]] # 1-P2/4
  - [-1, 2, C3k2, [256, False, 0.25]]
  - [-1, 1, Conv, [256, 3, 2]] # 3-P3/8
  - [-1, 2, C3k2, [512, False, 0.25]]
  - [-1, 1, Conv, [512, 3, 2]] # 5-P4/16
  - [-1, 2, C3k2, [512, True]]
  - [-1, 1, Conv, [1024, 3, 2]] # 7-P5/32
  - [-1, 2, C3k2, [1024, True]]
  - [-1, 1, SPPF, [1024, 5]] # 9
  - [-1, 2, C2PSA, [1024]] # 10

# YOLO11n head
head:
  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 6], 1, Concat, [1]] # cat backbone P4
  - [-1, 2, C3k2_CAA, [512, False]] # 13

  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 4], 1, Concat, [1]] # cat backbone P3
  - [-1, 2, C3k2_CAA, [256, False]] # 16 (P3/8-small)

  - [-1, 1, Conv, [256, 3, 2]]
  - [[-1, 13], 1, Concat, [1]] # cat head P4
  - [-1, 2, C3k2_CAA, [512, False]] # 19 (P4/16-medium)

  - [-1, 1, Conv, [512, 3, 2]]
  - [[-1, 10], 1, Concat, [1]] # cat head P5
  - [-1, 2, C3k2_CAA, [1024, True]] # 22 (P5/32-large)

  - [[16, 19, 22], 1, Segment, [nc, 32, 256]] # Segment(P3, P4, P5)
  • 旋转目标检测
# Ultralytics YOLO ????, AGPL-3.0 license
# YOLO11 object detection model with P3-P5 outputs. For Usage examples see https://docs.ultralytics.com/tasks/detect

# Parameters
nc: 80 # number of classes
scales: # model compound scaling constants, i.e. 'model=yolo11n.yaml' will call yolo11.yaml with scale 'n'
  # [depth, width, max_channels]
  n: [0.50, 0.25, 1024] # summary: 319 layers, 2624080 parameters, 2624064 gradients, 6.6 GFLOPs
  s: [0.50, 0.50, 1024] # summary: 319 layers, 9458752 parameters, 9458736 gradients, 21.7 GFLOPs
  m: [0.50, 1.00, 512] # summary: 409 layers, 20114688 parameters, 20114672 gradients, 68.5 GFLOPs
  l: [1.00, 1.00, 512] # summary: 631 layers, 25372160 parameters, 25372144 gradients, 87.6 GFLOPs
  x: [1.00, 1.50, 512] # summary: 631 layers, 56966176 parameters, 56966160 gradients, 196.0 GFLOPs

# YOLO11n backbone
backbone:
  # [from, repeats, module, args]
  - [-1, 1, Conv, [64, 3, 2]] # 0-P1/2
  - [-1, 1, Conv, [128, 3, 2]] # 1-P2/4
  - [-1, 2, C3k2, [256, False, 0.25]]
  - [-1, 1, Conv, [256, 3, 2]] # 3-P3/8
  - [-1, 2, C3k2, [512, False, 0.25]]
  - [-1, 1, Conv, [512, 3, 2]] # 5-P4/16
  - [-1, 2, C3k2, [512, True]]
  - [-1, 1, Conv, [1024, 3, 2]] # 7-P5/32
  - [-1, 2, C3k2, [1024, True]]
  - [-1, 1, SPPF, [1024, 5]] # 9
  - [-1, 2, C2PSA, [1024]] # 10

# YOLO11n head
head:
  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 6], 1, Concat, [1]] # cat backbone P4
  - [-1, 2, C3k2_CAA, [512, False]] # 13

  - [-1, 1, nn.Upsample, [None, 2, "nearest"]]
  - [[-1, 4], 1, Concat, [1]] # cat backbone P3
  - [-1, 2, C3k2_CAA, [256, False]] # 16 (P3/8-small)

  - [-1, 1, Conv, [256, 3, 2]]
  - [[-1, 13], 1, Concat, [1]] # cat head P4
  - [-1, 2, C3k2_CAA, [512, False]] # 19 (P4/16-medium)

  - [-1, 1, Conv, [512, 3, 2]]
  - [[-1, 10], 1, Concat, [1]] # cat head P5
  - [-1, 2, C3k2_CAA, [1024, True]] # 22 (P5/32-large)

  - [[16, 19, 22], 1, OBB, [nc, 1]] # OBB(P3, P4, P5)

温馨提示:本文只是对yolo11基础上添加模块,如果要对yolo11n/l/m/x进行添加则只需要指定对应的depth_multiple 和 width_multiple


# YOLO11n
depth_multiple: 0.50  # model depth multiple
width_multiple: 0.25  # layer channel multiple
max_channel:1024
 
# YOLO11s
depth_multiple: 0.50  # model depth multiple
width_multiple: 0.50  # layer channel multiple
max_channel:1024
 
# YOLO11m
depth_multiple: 0.50  # model depth multiple
width_multiple: 1.00  # layer channel multiple
max_channel:512
 
# YOLO11l 
depth_multiple: 1.00  # model depth multiple
width_multiple: 1.00  # layer channel multiple
max_channel:512 
 
# YOLO11x
depth_multiple: 1.00  # model depth multiple
width_multiple: 1.50 # layer channel multiple
max_channel:512

2.4 在task.py中进行注册

关键步骤四:在parse_model函数中进行注册,添加C3k2_CAA, C3k2_CAA_v2

先在task.py导入函数

然后在task.py文件下找到parse_model这个函数,如下图,添加C3k2_CAA, C3k2_CAA_v2

1. 

2.

2.5 执行程序

关键步骤五: 在ultralytics文件中新建train.py,将model的参数路径设置为yolo11_C3k2_CAA.yaml的路径即可 【注意是在外边的Ultralytics下新建train.py】

from ultralytics import YOLO
import warnings
warnings.filterwarnings('ignore')
from pathlib import Path
 
if __name__ == '__main__':
 
 
    # 加载模型
    model = YOLO("ultralytics/cfg/11/yolo11.yaml")  # 你要选择的模型yaml文件地址
    # Use the model
    results = model.train(data=r"你的数据集的yaml文件地址",
                          epochs=100, batch=16, imgsz=640, workers=4, name=Path(model.cfg).stem)  # 训练模型

   ????运行程序,如果出现下面的内容则说明添加成功????  

                   from  n    params  module                                                arguments
  0                  -1  1       464  ultralytics.nn.modules.conv.Conv                      [3, 16, 3, 2]
  1                  -1  1      4672  ultralytics.nn.modules.conv.Conv                      [16, 32, 3, 2]
  2                  -1  1      6640  ultralytics.nn.modules.block.C3k2                     [32, 64, 1, False, 0.25]
  3                  -1  1     36992  ultralytics.nn.modules.conv.Conv                      [64, 64, 3, 2]
  4                  -1  1     26080  ultralytics.nn.modules.block.C3k2                     [64, 128, 1, False, 0.25]
  5                  -1  1    147712  ultralytics.nn.modules.conv.Conv                      [128, 128, 3, 2]
  6                  -1  1     87040  ultralytics.nn.modules.block.C3k2                     [128, 128, 1, True]
  7                  -1  1    295424  ultralytics.nn.modules.conv.Conv                      [128, 256, 3, 2]
  8                  -1  1    346112  ultralytics.nn.modules.block.C3k2                     [256, 256, 1, True]
  9                  -1  1    164608  ultralytics.nn.modules.block.SPPF                     [256, 256, 5]
 10                  -1  1    249728  ultralytics.nn.modules.block.C2PSA                    [256, 256, 1]
 11                  -1  1         0  torch.nn.modules.upsampling.Upsample                  [None, 2, 'nearest']
 12             [-1, 6]  1         0  ultralytics.nn.modules.conv.Concat                    [1]
 13                  -1  1    118080  ultralytics.nn.modules.models.C3k2_CAA.C3k2_CAA       [384, 128, 1, False]
 14                  -1  1         0  torch.nn.modules.upsampling.Upsample                  [None, 2, 'nearest']
 15             [-1, 4]  1         0  ultralytics.nn.modules.conv.Concat                    [1]
 16                  -1  1     35488  ultralytics.nn.modules.models.C3k2_CAA.C3k2_CAA       [256, 64, 1, False]
 17                  -1  1     36992  ultralytics.nn.modules.conv.Conv                      [64, 64, 3, 2]
 18            [-1, 13]  1         0  ultralytics.nn.modules.conv.Concat                    [1]
 19                  -1  1     93504  ultralytics.nn.modules.models.C3k2_CAA.C3k2_CAA       [192, 128, 1, False]
 20                  -1  1    147712  ultralytics.nn.modules.conv.Conv                      [128, 128, 3, 2]
 21            [-1, 10]  1         0  ultralytics.nn.modules.conv.Concat                    [1]
 22                  -1  1    378880  ultralytics.nn.modules.models.C3k2_CAA.C3k2_CAA_v2    [384, 256, 1, True]
 23        [16, 19, 22]  1    464912  ultralytics.nn.modules.head.Detect                    [80, [64, 128, 256]]
YOLO11_C3k2_CAA summary: 340 layers, 2,641,040 parameters, 2,641,024 gradients, 6.7 GFLOPs

3.修改后的网络结构图

4. 完整代码分享

主页侧边联系方式获取

5. GFLOPs

关于GFLOPs的计算方式可以查看百面算法工程师 | 卷积基础知识——Convolution

未改进的YOLO11n GFLOPs

改进后的GFLOPs

6. 进阶

可以与其他的注意力机制或者损失函数等结合,进一步提升检测效果

7.总结

通过以上的改进方法,我们成功提升了模型的表现。这只是一个开始,未来还有更多优化和技术深挖的空间。在这里,我想隆重向大家推荐我的专栏——<专栏地址:YOLO11入门 + 改进涨点——点击即可跳转 欢迎订阅>。这个专栏专注于前沿的深度学习技术,特别是目标检测领域的最新进展,不仅包含对YOLO11的深入解析和改进策略,还会定期更新来自各大顶会(如CVPR、NeurIPS等)的论文复现和实战分享。

为什么订阅我的专栏? ——专栏地址:YOLO11入门 + 改进涨点——点击即可跳转 欢迎订阅

  1. 前沿技术解读:专栏不仅限于YOLO系列的改进,还会涵盖各类主流与新兴网络的最新研究成果,帮助你紧跟技术潮流。

  2. 详尽的实践分享:所有内容实践性也极强。每次更新都会附带代码和具体的改进步骤,保证每位读者都能迅速上手。

  3. 问题互动与答疑:订阅我的专栏后,你将可以随时向我提问,获取及时的答疑

  4. 实时更新,紧跟行业动态:不定期发布来自全球顶会的最新研究方向和复现实验报告,让你时刻走在技术前沿。

专栏适合人群:

  • 对目标检测、YOLO系列网络有深厚兴趣的同学

  • 希望在用YOLO算法写论文的同学

  • 对YOLO算法感兴趣的同学等

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